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	<meta charset="UTF-8">
	<title>Document</title>
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<body>
	<h1 align="center">用户注册许可协议</h1>
	<p align="center">...</p>
	<p align="center">...</p>
	<p align="center">...</p>	
	<p align="center">
		<input type="button" value="我同意(5)" disabled id="agree" onclick="nextStep()">
	</p>
</body>
	<script>
		function nextStep(){
			location.href = 'http://www.baidu.com';
		}
		var i = 4;
		var timeId = window.setInterval(function(){
			document.getElementById('agree').value = '我同意(' + i + ')';			
			if(i==0){
				window.clearInterval(timeId);
				document.getElementById('agree').value = '我同意';
				document.getElementById('agree').disabled = false;
			}
			i--;
		},1000);
	</script>
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